Electrical connector housing with means producing contact wipe

ABSTRACT

Electrical connector apparatus including a mechanically actuated linear cam bar adapted to provide contact closure and contact wipe for the contacting elements connecting to the edge connectors of a printed circuit board. A frame supporting the main circuit board includes a drawbolt device which causes a linear cam bar to move in a forward and backward direction. Cam surfaces on the cam bar transmit a vertical downward movement to a connector housing to cause the contacts to make with the edge connectors of a printed circuit card inserted therein. After the contacts are made, sets of pins operated by a second cam surface on the cam bar function to move the card vertically upward to produce a wiping action between the edge connector on the card and the pin contacts in the connecting board.

United States Patent [72] Inventors Theodore F. Flavin Owego;

John B. Harris. Endicott; John R. Mankus, Endicott, all of, N.Y. [2 l]Appl. No. 863,130 [22] Filed Oct. 2, 1969 (45] Patented June 22, 1971[73] Assignee International Business Machines Corporation Armonk, N.Y.

[ 54] ELECTRICAL CONNECTOR HOUSING WITH MEANS PRODUCING CONTACT WIPE 5Claims, 7 Drawing Figs.

[52] US. Cl.... 339/75 MP, 339/95 R, 339/176 MP [51] Int. Cl'..;H01r'l3/54 [50] Field ofSearch 339/74, 75, 95, 176

[56] References Cited UNITED STATES PATENTS 2,594,737 4/1952 Cunningham339/18 2,748,364 5/1956 Kamm 339/75 MP 2,879,493 339/18 B 3/1959 Bender2,956,258 10/1960 Raddin 339/75 MP 2,975,390 3/1961 Cardascia et al.339/45 M OTHER REFERENCES IBM TECHNICAL DISCLOSURE BULLETIN Vol. 10, No.11,4/1968, p. 1695,Schmieg et al.

Primary Examinerlan A. Calvert Assistant Examiner-Joseph H. McGlynnAttorneys-Hanifin and Jancin and Charles S. Neave ABSTRACT: Electricalconnector apparatus including a mechanically actuated linear cam baradapted to provide contact closure and contact wipe for the contactingelements connecting to the edge connectors of a printed circuit board. Aframe supporting the main circuit board includes a drawbolt device whichcauses a linear cam bar to move in a forward and backward direction. Camsurfaces on the cam bar transmit a vertical downward movement to -aconnector housing to cause the contacts to make with the edge connectorsof a printed circuit card inserted therein. After the contacts are made,sets of pins operated by a second cam surface on the cam bar func-PATENTEUJUNZZIBYI 3,587,031

sum 1 OF 2 LINEAR CAM HOTION FIG. 6

IN VE N TORS THEODORE F. FLAVIN JOHN B. HARRIS JOHN R. MANKUS PATENTEUJUN22 19m SHEET 2 [IF 2 FIG. 5

Lam-22 Lulu ELECTRICAL CONNECTOR HOUSING WITH MEANS PRODUCING CONTACTWIPE BACKGROUND OF THE INVENTION 1. Field of the Invention Thisinvention relates to electrical connector apparatus of the type adaptedto complete-a plurality of circuits substantially simultaneously withactuating apparatus for forcibly producing contact wipe after a circuitboard or the like has been introduced into a connector housing.

2. Description of the Prior Art Various arrangements exist in the priorart for releasably receiving, holding and making electrical edgeconnections with printed circuit boards or panels having a plurality ofprinted circuits thereon. Such connector devices are finding anincreasing number of applications in data processing equipment as theelectrical and control circuits become more numerous. The boards mayhave to be inserted and withdrawn from the edge connectors many times.The ever-increasing trend towards microminiaturization, diminutive wiresand close lead spacing, as well as the fragile nature of the boards andcircuitry thereon, introduces considerable difficulty in the handling ofthe boards. Further, means to provide a wipe action of sufficientmagnitude to. remove any surface oxide film, dust particles or otherforeign substances, on the connector members to enable a suitablecontact of low electrical resistance, has introduced other problems suchas reliability in the electrical connections and the manufacturing ofsuch apparatus within acceptable economic tolerances.

SUMMARY OF THE INVENTION A primary object of the present invention is toovercome the above-noted difficulties by providing a unique electricalconnector housing with mechanical actuated apparatus for producing thecontact wipe after a circuit board or the like has been inserted intothe connector housing. The present invention provides a circuit boardedge connector assembly comprising a connector housing adapted toaccommodate one or more such printed circuit boards and provided with aplurality of connectors for connecting with the edge connectors of theprinted circuit boards, and a mechanically actuated linear cam baradapted to first move the housing so as to cause the contact closurefollowed by the movement of other means that function to motivate theprinted circuit boards in a manner that will produce wipe action betweenthe edge connectors on the printed circuit boards and the connectorswithin the connector housing. v

The foregoing and other objects, features and advantages of theinvention will be apparent from the following more particulardescription of a preferred embodiment of the invention, as illustratedin the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a isometric and fragmentaryview of an electrical connector housing'assembly with means to producecontact closure and wipe according to the present invention.

FIG. 2 is a isometric view of the cam actuated connector housing pulland printed circuit board push mechanism.

FIG. 3 is a side elevational view with partial fragmentary showing of aportion of the electrical connecto'r housing assembly and illustratingthe connector housing in an open position.

FIG. 4 is a side elevational view of the electrical connector housingassembly with the housing and mechanism in a contact closed before wipeposition.

FIG. 5 is a side elevational view of the electrical connector housingassembly with the housing and apparatus in a contact closed after wipeposition.

FIG. 6 is an enlarged showing of a portion of the linear cam barillustrating the inclined planes principle for actuating the connectorhousing through three discrete positions.

FIG. 7 is a sectional view along the line 7-7 of FIG. 3 showing theactuation of pin connectors by the connector housing so as to contactthe edge connectors of a printed circuit card.

DESCRIPTION OF THE PREFERRED EMBODIMENT Structure Referring to thedrawings, in FIG. 1 there is shown a preferred embodiment for anelectrical connector housing assembly adapted to accommodate one or moreinsertable printed circuit boards or cards in end-to-end relationshipthereby fonning a row of printed circuit cards. It may be noted thatwhile only a single row of printed circuits cards is shown, otheraccommodating arrangements are possible for a plurality of rows ofprinted circuit cards in side-by-side relationship. The assemblycomprises a frame 10 to which is attached a dielectric element 11 thatin turn has affixed thereto a pin interface l2 and a pin carrier 13. Thepin carrier 13 supports opposing rows of pin connectorelements 14 thatare adapted to make electrical connections with the edge connectors 15aof a printed circuit board 15 inserted between the pairs of opposingrows of pins 14. A single row of pins 14 could be adapted to connect oneside of a printed circuit board or card without departing from thespirit of this invention. The function of the pin interface 12 and thepin carrier 13 is to enable electrical connections with other equipmentof a data processing system not shown herein.

The connector housing assembly also includes a plurality of pinseparator elements 16 of dielectric material embraced by housing 17. Thehousing 17 is attached at various points throughout its length tohousing drawbar elements 18 by means of screws 19.

Referring to FIG. 2, the housing drawbar assembly comprises the drawbarelement 18 affixed to a shaft 20 on which the pulldown cam element 21 isslidably mounted and retained by an adjust nut 22. A contact wipe pusherassembly including a pair of card push pins 23 attached to a push camelement 24 is also slidably supported on shaft 20. The housing drawbarand contact wipe pusher assemblies are movably mounted within aperturesin the framelO.

A linear cam bar 25 is movably mounted within a lower portion of frame10. A cam actuating drawbolt 26 is rotatably supported in the endportion of the frame 10 and functions to provide the linear cam bar 25with a forward and backward motion. The linear cam bar 25 is retainedwithin frame 10 by means of guide plate 27 Operation In FIG. 3 theelectrical connector housing assembly is shown with the linear cam bar25 in its number one or opened position (see also FIG. 6) in which thelinear cam bar 25 is moved to its rightmost location. In this position,the housing 17 is ready to receive a printed circuit card or board 15with its edge connector edge downward and inserted between the opposingrows of connector pins 14. When the printed circuit card 15 is fullyinserted manually and under biasing means (not shown) applied to theopposite edge of the printed circuit card, the outward corners and loweredge of the card will come in touch with the upper end of the card pushpins 23. As the cam actuating bolt 26 is rotated so as to move thelinear cam bar 25 towards the left, the housing pull down cam 21 willrise on the inclined ramp of the lower side of the linear cam bar 25thereby pulling the housing 17 in a downward direction and forcing thepin connectors 14 into electrical contact with the edge connectors onthe printed circuit card 15 (FIG. 7). When the pull down cam 21completed its climb of the inclined ramp, the pin connectors will befully closed, which is position 2 of FIG. 6.

Now, as the linear cam bar 25 continues to move in the leftwarddirection the push cam element 24 will rise along the inclined ramp ofthe upper surface of the linear cam bar 25 thereby causing the contactwipe pusher assembly to move up wards. This action causes the printedcircuit card 15 to be forcibly urged upwards thereby providing a wipeaction of sufficient magnitude to remove any surface oxide film, dustparticles, or other foreign substances on the electrical connectingmembers so as to produce low electrical resistance between thecooperating electrical members.

To release the printed circuit cards 15, the cam actuating bolt 26 isrotated in the opposite direction. As the housing pull down cam 21approaches the position to open point, position 1 (FIG. 6) the housingbias spring 30 will cause the housing pull down assembly to move in theupward direction thereby releasing the printed circuit card 15.

A salient feature of the structure and its operation is that edgeconnectors on a printed circuit card are: (1) not subjected tofrictional wear during insertion into the housing; and (2) aftercontacts are closed there is only a minimum of frictional wear, thatwhich is necessary to produce contact wipe; and (3) there is nofrictional wear during opening of the contacts and removal of the cardfrom the housing. This enables a much longer and useful card life.

While the invention has been particularly shown and described withreference to a preferred embodiment thereof, it will be understood bythose skilled in the art that the foregoing and other changes in formand details may be made therein.

We claim:

l. A multiple contact connector assembly for providing low andsubstantially uniform contact resistance between the individual contactsof the assembly and conductor elements of a printed circuit card, thecombination comprising:

a. a frame,

b. a pin interface element attached to the frame,

c. a pin carrier which supports opposing rows of pin connector elementsthat are adapted to make electrical connections with the edge conductorsof a printed circuit card inserted between the pairs of opposing rows ofpin connector elements with the pin connector elements beingelectrically coupled to the pin interface element,

d. a connector housing assembly embracing the pin connector elements,

e. a first cam controlled means connected with said connector housingassembly for moving the housing assembly in a direction that will biasthe pin connectors into electrical contact with the edge conductors onthe printed circuit card, and

f. a second cam controlled means adapted to engage an innermost edge ofthe printed circuit card and forcibly urge it between the closedconnecting elements to remove any foreign substances on the electricalconnecting elements and thereby produce low electrical resistancebetween the cooperating electrical elements.

2. A multiple contact connector assembly as defined in claim 1 includingthird cam controlled means for releasably disconnecting the printedcircuit card from the pin connector elements.

3. Electrical edge connecting apparatus for a plurality of printedcircuit cards and the like, the combination comprising:

a. a base member,

b. an electrical pin carrier board attached to the base member andhaving opposing rows of pin connector elements extending from the boardthat are adapted to make electrical connections with edge conductors ofthe printed circuit cards inserted between the pairs of opposing rows ofpin connector elements,

c. a housing member embracing the edge connecting pins on the pincarrier board,

d. a linear cam bar slidably mounted within the base member,

e. means to actuate the linear cam bar in a forward and backwarddirection,

f. a first means controlled by the linear cam bar when moved in aforward direction coupled with the housing member and operative to causethe housingmember to bias the free ends of the edge connecting pins intocontact with edge connecting elements of the printed circuit cardsinserted between the opposing rows of connecting pins,

g. a second means controlled by the linear cam bar when moved in aforward direction and operative to engage the edges of the printedcircuit cards and forcibly urge them between the closed contact elementsto remove any foreign substance and thereby produce low electricalresistance between the cooperating electrical elements.

4. Electrical edge connecting apparatus for a plurality of printedcircuit cards and the like as defined in claim 3 wherein the first meanscontrolled by the movement of the linear cam bar in a backward directionis operative to releasably disconnect the printed circuit cards from thepin connector elements.

5. Electrical edge connecting apparatus for a plurality of printedcircuit cards and the like as defined in claim 4 further including a pininterface element electrically connected with the pin connector elementsin the pin carrier board and which functions to establish electricalconnections with other electrical equipment.

1. A multiple contact connector assembly for providing low andsubstantially uniform contact resistance between the individual contactsof the assembly and conductor elements of a printed circuit card, thecombination comprising: a. a frame, b. a pin interface element attachedto the frame, c. a pin carrier which supports opposing rows of pinconnector elements that are adapted to make electrical connections withthe edge conductors of a printed circuit card inserted between the pairsof opposing rows of pin connector elements with the pin connectorelements being electrically coupled to the pin interface element, d. aconnector housing assembly embracing the pin connector elements, e. afirst cam controlled means connected with said connector housingassembly for moving the housing assembly in a direction that will biasthe pin connectors into electrical contact with the edge conductors onthe printed circuit card, and f. a second cam controlled means adaptedto engage an innermost edge of the printed circuit card and forciblyurge it between the closed connecting elements to remove any foreignsubstances on the electrical connecting elements and thereby produce lowelectrical resistance between the cooperating electrical elements.
 2. Amultiple contact connector assembly as defined in claim 1 includingthird cam controlled Means for releasably disconnecting the printedcircuit card from the pin connector elements.
 3. Electrical edgeconnecting apparatus for a plurality of printed circuit cards and thelike, the combination comprising: a. a base member, b. an electrical pincarrier board attached to the base member and having opposing rows ofpin connector elements extending from the board that are adapted to makeelectrical connections with edge conductors of the printed circuit cardsinserted between the pairs of opposing rows of pin connector elements,c. a housing member embracing the edge connecting pins on the pincarrier board, d. a linear cam bar slidably mounted within the basemember, e. means to actuate the linear cam bar in a forward and backwarddirection, f. a first means controlled by the linear cam bar when movedin a forward direction coupled with the housing member and operative tocause the housing member to bias the free ends of the edge connectingpins into contact with edge connecting elements of the printed circuitcards inserted between the opposing rows of connecting pins, g. a secondmeans controlled by the linear cam bar when moved in a forward directionand operative to engage the edges of the printed circuit cards andforcibly urge them between the closed contact elements to remove anyforeign substance and thereby produce low electrical resistance betweenthe cooperating electrical elements.
 4. Electrical edge connectingapparatus for a plurality of printed circuit cards and the like asdefined in claim 3 wherein the first means controlled by the movement ofthe linear cam bar in a backward direction is operative to releasablydisconnect the printed circuit cards from the pin connector elements. 5.Electrical edge connecting apparatus for a plurality of printed circuitcards and the like as defined in claim 4 further including a pininterface element electrically connected with the pin connector elementsin the pin carrier board and which functions to establish electricalconnections with other electrical equipment.